19 resultados para 423

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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Calliostoma tupinamba is a new species from Southeastern Brazil, ranging from southern Rio de Janeiro to northern Sao Paulo, and found only on coastal islands, on rocks and sessile invertebrates at 3 to 5 meters of depth. Shell and soft part morphology is described here in detail. Calliostoma tupinamba is mainly characterized by a depressed trochoid shell; eight slightly convex whorls; a sharply suprasutural carina starting on the third whorl and forming a peripheral rounded keel; and a whitish, funnel-shaped and deep umbilicus, measuring about 5%-10% of maximum shell width. Calliostoma tupinamba resembles C. bullisi Clench & Turner, 1960 in shape, but differs from it in being taller and wider, having a smaller umbilicus and lacking a strong and large innermost spiral cord at its base. Finally, an identification key of Brazilian Calliostoma species is presented.

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In the past few decades detailed observations of radio and X-ray emission from massive binary systems revealed a whole new physics present in such systems. Both thermal and non-thermal components of this emission indicate that most of the radiation at these bands originates in shocks. O and B-type stars and WolfRayet (WR) stars present supersonic and massive winds that, when colliding, emit largely due to the freefree radiation. The non-thermal radio and X-ray emissions are due to synchrotron and inverse Compton processes, respectively. In this case, magnetic fields are expected to play an important role in the emission distribution. In the past few years the modelling of the freefree and synchrotron emissions from massive binary systems have been based on purely hydrodynamical simulations, and ad hoc assumptions regarding the distribution of magnetic energy and the field geometry. In this work we provide the first full magnetohydrodynamic numerical simulations of windwind collision in massive binary systems. We study the freefree emission characterizing its dependence on the stellar and orbital parameters. We also study self-consistently the evolution of the magnetic field at the shock region, obtaining also the synchrotron energy distribution integrated along different lines of sight. We show that the magnetic field in the shocks is larger than that obtained when the proportionality between B and the plasma density is assumed. Also, we show that the role of the synchrotron emission relative to the total radio emission has been underestimated.

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BACKGROUND: Actinic cheilitis, a common disease caused by chronic solar exposure and tobacco use, is considered a premalignant lesion with potential to develop into squamous cell carcinoma. Some of the available treatments are invasive, have unaesthetic results and require multiple sessions. OBJECTIVE: To assess the efficacy of a therapy and its cosmetic results. METHODS: In this uncontrolled clinical trial a single photodynamic therapy (PDT) session using 16% methyl-aminolevulinate was performed on actinic cheilitis of the lower lip. A standardized questionnaire was applied in order to assess the clinical improvement from the patients' point of view and the satisfaction with the treatment. Anatomopathological evaluation was performed before the treatment and two months afterwards. RESULTS: The sample was composed of 19 patients (10 males and 9 females), phototypes I to III, with average age of 62 years. Main adverse effects were: sudden pain, scabs, herpes flare-up, and edema. The average score of pain during the procedure was 5,8+2,9. At the final assessment the patients reported improvement of 80% and satisfaction of 85% (p<0.01). Anatomopathological analysis showed a significant decrease of dysplasia (p=0.03) in spite of its presence in 84% of cases. There was no significant correlation between the level of dysplasia with either the subjective impression of clinical improvement (p=0.82) or with the patients' final satisfaction (p=0.96). CONCLUSION: PDT is effective in the treatment of actinic cheilitis, but it is associated with a significant level of pain. Due to the persistence of dysplasia, more research needs to be done in order to define the ideal number of sessions for the effective treatment of these lesions.

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While the presence of discs around classical Be stars is well established, their origin is still uncertain. To understand what processes result in the creation of these discs and how angular momentum is transported within them, their physical properties must be constrained. This requires comparing high spatial and spectral resolution data with detailed radiative transfer modelling. We present a high spectral resolution, R similar to 80 000, sub-milliarcsecond precision, spectroastrometric study of the circumstellar disc around the Be star beta CMi. The data are confronted with 3D, non-local thermodynamic equilibrium radiative transfer calculations to directly constrain the properties of the disc. Furthermore, we compare the data to disc models featuring two velocity laws: Keplerian, the prediction of the viscous disc model, and angular momentum conserving rotation. It is shown that the observations of beta CMi can only be reproduced using Keplerian rotation. The agreement between the model and the observed spectral energy distribution, polarization and spectroastrometric signature of beta CMi confirms that the discs around Be stars are well modelled as viscous decretion discs.

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Lipid peroxidation (LPO) has been associated with periodontal disease, and the evaluation of malondialdehyde (MDA) in the gingival crevicular fluid (GCF), an inflammatory exudate from the surrounding tissue of the periodontium, may be useful to clarify the role of LPO in the pathogenesis of periodontal disease. We describe the validation of a method to measure MDA in the GCF using high-performance liquid chromatography. MDA calibration curves were prepared with phosphate-buffered solution spiked with increasing known concentrations of MDA. Healthy and diseased GCF samples were collected from the same patient to avoid interindividual variability. MDA response was linear in the range measured, and excellent agreement was observed between added and detected concentrations of MDA. Samples' intra- and interday coefficients of variation were below 6.3% and 12.4%, respectively. The limit of quantitation (signal/noise = 5) was 0.03 mu M. When the validated method was applied to the GCF, excellent agreement was observed in the MDA quantitation from healthy and diseased sites, and diseased sites presented more MDA than healthy sites (P < 0.05). In this study, a validated method for MDA quantitation in GCF was established with satisfactory sensitivity, precision, and accuracy. (C) 2012 Elsevier Inc. All rights reserved.

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We evaluated the effects of air-drying distance and bond surface area on the shear bond strength of a 2-step etch-and-rinse adhesive. A total of 120 bovine anterior teeth were equally divided into 6 main groups based on bonding surface area. The main groups were divided into sub-groups (n = 5) according to air-drying distance. The shear strength was determined using a universal testing machine at a crosshead speed of 0.5 mm/min. The averaged results were subjected to two-way ANOVA and Tukey's test (alpha = 0.05). Two-way ANOVA testing identified no significant cross-product interactions (p > 0.05), but the main factors of area (p < 0.0001) and air-drying distance (p < 0.00001) significantly affected the mean bond strength. Shorter air-drying distances improved bond strength, and increased surface area decreased the bond strength.

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In this paper we diagnose the genus Sabroskya Schlinger, 1960 and describe Sabroskya schlingeri sp. n. from Malawi. We also provide dichotomous keys to species of Sabroskya and to world genera of the subfamily Acrocerinae, both extant and extinct.

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We report the results from the temporal and spectral analysis of an XMMNewton observation of Nova Centauri 1986 (V842 Cen). We detect a period at 3.51 +/- 0.4 h in the EPIC data and at 4.0 +/- 0.8 h in the Optical Monitor (OM) data. The X-ray spectrum is consistent with the emission from an absorbed thin thermal plasma with a temperature distribution given by an isobaric cooling flow. The maximum temperature of the cooling flow model is keV. Such a high temperature can be reached in a shocked region and, given the periodicity detected, most likely arises in a magnetically channelled accretion flow characteristic of intermediate polars. The pulsed fraction of the 3.51-h modulation decreases with energy as observed in the X-ray light curves of magnetic cataclysmic variables, possibly due either to occultation of the accretion column by the white dwarf body or phase-dependent to absorption. We do not find the 57-s white dwarf spin period, with a pulse amplitude of 4 mmag, reported by Woudt et al. in either the OM data, which are sensitive to pulse amplitudes ?0.03 mag, or the EPIC data, sensitive to pulse fractions p? 14 +/- 2 per cent.

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Molecular findings that confirmed the participation of ovine herpesvirus 2 (OVH-2) in the lesions that were consistent with those observed in malignant catarrhal fever of cattle are described. Three mixed-breed cattle from Rio Grande do Norte state demonstrated clinical manifestations that included mucopurulent nasal discharge, corneal opacity and motor incoordination. Routine necropsy examination demonstrated ulcerations and hemorrhage of the oral cavity, corneal opacity, and lymph node enlargement. Significant histopathological findings included widespread necrotizing vasculitis, non-suppurative meningoencephalitis, lymphocytic interstitial nephritis and hepatitis, and thrombosis. PCR assay performed on DNA extracted from kidney and mesenteric lymph node of one animal amplified a product of 423 base pairs corresponding to a target sequence within the ovine herpesvirus 2 (OVH-2) tegument protein gene. Direct sequencing of the PCR products, from extracted DNA of the kidney and mesenteric lymph node of one cow, amplified the partial nucleotide sequences (423 base pairs) of OVH-2 tegument protein gene. Blast analysis confirmed that these sequences have 98-100% identity with similar OVH-2 sequences deposited in GenBank. Phylogenetic analyses, based on the deduced amino acid sequences, demonstrated that the strain of OVH-2 circulating in ruminants from the Brazilian states of Rio Grande do Norte and Minas Gerais are similar to that identified in other geographical locations. These findings confirmed the active participation of OVH-2 in the classical manifestations of sheep associated malignant catarrhal fever.

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We report a study of the stellar content of the near-infrared (NIR) cluster [DBS2003] 157 embedded in the extended H ii region GAL 331.31-00.34, which is associated with the IRAS source 16085-5138. JHK photometry was carried out in order to identify potential ionizing candidates, and the follow-up NIR spectroscopy allowed the spectral classification of some sources, including two O-type stars. A combination of NIR photometry and spectroscopy data was used to obtain the distance of these two stars, with the method of spectroscopic parallax: IRS 298 (O6 V, 3.35 +/- 0.61 kpc) and IRS 339 (O9 V, 3.24 +/- 0.56 kpc). Adopting the average distance of 3.29 +/- 0.58 kpc and comparing the Lyman continuum luminosity of these stars with that required to account for the radio continuum flux of the H ii region, we conclude that these two stars are the ionizing sources of GAL 331.31-00.34. Young stellar objects (YSOs) were searched by using our NIR photometry and mid-infrared (MIR) data from the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) survey. The analysis of NIR and MIR colourcolour diagrams resulted in 47 YSO candidates. The GLIMPSE counterpart of IRAS 16085-5138, which presents IRAS colour indices compatible with an ultracompact H ii region, has been identified. The analysis of its spectral energy distribution between 2 and m revealed that this source shows a spectral index a= 3.6 between 2 and m, which is typical of a YSO immersed in a protostellar envelope. Lower limits to the bolometric luminosity and the mass of the embedded protostar have been estimated as L= 7.7 x 10(3) L? and M= 10 M?, respectively, which correspond to a B0B1 V zero-age main sequence star.

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The oxygen reduction reaction (ORR) was studied in KOH electrolyte on carbon supported epsilon-manganese dioxide (epsilon-MnO2/C). The epsilon-MnO2/C catalyst was prepared via thermal decomposition of manganese nitrate and carbon powder (Vulcan XC-72) mixtures. X-ray powder diffraction (XRD) measurements were performed in order to determine the crystalline structure of the resulting composite, while energy dispersive X-ray analysis (EDX) was used to evaluate the chemical composition of the synthesized material. The electrochemical studies were conducted using cyclic voltammetry (CV) and quasi-steady state polarization measurements carried out with an ultra thin layer rotating ring/disk electrode (RRDE) configuration. The electrocatalytic results obtained for 20% (w/w) Pt/C (E-TEK Inc., USA) and alpha-MnO2/C for the ORR, considered as one of the most active manganese oxide based catalyst for the ORR in alkaline media, were included for comparison. The RRDE results revealed that the ORR on the MnO2 catalysts proceeds preferentially through the complete 4e(-) reduction pathway via a 2 plus 2e(-) reduction process involving hydrogen peroxide as an intermediate. A benchmark close to the performance of 20% (w/w) Pt/C (E-TEK Inc., USA) was observed for the epsilon-MnO2/C material in the kinetic control region, superior to the performance of alpha-MnO2/C, but a higher amount of HO2- was obtained when epsilon-MnO2/C was used as catalyst. The higher production of hydrogen peroxide on epsilon-MnO2/C was related to the presence of structural defects, typical of this oxide, while the better catalytic performance in the kinetic control region compared to alpha-MnO2/C was related with the higher electrochemical activity for the proton insertion kinetics, which is a structure sensitive process. (C) 2012 Elsevier Ltd. All rights reserved.

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Most atypical antipsychotic drugs (APDs), e. g. risperidone (RIS), produce more extensive blockade of brain serotonin (5-HT)(2A) than dopamine (DA) D-2 receptors. This distinguishes them from typical APDs, e.g. haloperidol (HAL). Our objective was to test the hypothesis that augmentation of low doses of RIS or HAL (2 mg/day) with pimavanserin (PIM), a selective 5-HT2A inverse agonist, to enhance 5-HT2A receptor blockade, can achieve efficacy comparable to RIS, 6 mg/day, but with lesser side effects. In a multi-center, randomized, double-blind, 6 week trial, 423 patients with chronic schizophrenia experiencing a recent exacerbation of psychotic symptoms were randomized to RIS2mg + placebo (RIS2PBO), RIS2mg + PIM20mg (RIS2PIM), RIS6mg + PBO (RIS6PBO), HAL2mg + PBO (HAL2PBO), or HAL2mg + PIM20mg (HAL2PIM). Improvement in psychopathology was measured by the PANSS and CGI-S. The reduction in PANSS Total Score with RIS2PIM at endpoint was significantly greater than RIS2PBO: -23.0 vs. -16.3 (p = 0.007), and not significantly different from the RIS6PBO group: -23.2 points. The percentage of patients with >= 20% improvement at day 15 in the RIS2PIM group was 62.3%, significantly greater than the RIS6PBO (42.1%; p = 0.01) and the RIS2PBO groups (37.7%; p = 0.002). Weight gain and hyperprolactinemia were greater in the RIS6PBO group than the RIS2PIM group but there was no difference in extrapyramidal side effects (EPS). HAL2PBO and HAL2PIM were not significantly different from each other in efficacy but HAL2PIM had less EPS at end point. Both HAL groups and RIS6PBO showed equal improvement in psychopathology at endpoint, indicating HAL 2 mg/day is effective to treat an acute exacerbation in chronic schizophrenia patients. In conclusion, a sub-effective RIS dose combined with PIM to enhance 5-HT2A receptor blockade provided faster onset of action, and at endpoint, equal efficacy and better safety, compared to standard dose RIS. These results support the conclusion that 5-HT2A receptor blockade is a key component of the action of some atypical APDs and can reduce EPS due to a typical APD. (C) 2012 Elsevier B.V. All rights reserved.

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In this article, we present a new control chart for monitoring the covariance matrix in a bivariate process. In this method, n observations of the two variables were considered as if they came from a single variable (as a sample of 2n observations), and a sample variance was calculated. This statistic was used to build a new control chart specifically as a VMIX chart. The performance of the new control chart was compared with its main competitors: the generalized sampled variance chart, the likelihood ratio test, Nagao's test, probability integral transformation (v(t)), and the recently proposed VMAX chart. Among these statistics, only the VMAX chart was competitive with the VMIX chart. For shifts in both variances, the VMIX chart outperformed VMAX; however, VMAX showed better performance for large shifts (higher than 10%) in one variance.

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Bee venom (BV) allergy is potentially dangerous for allergic individuals because a single bee sting may induce an anaphylactic reaction, eventually leading to death. Currently, venom immunotherapy (VIT) is the only treatment with long-lasting effect for this kind of allergy and its efficiency has been recognized worldwide. This therapy consists of subcutaneous injections of gradually increasing doses of the allergen. This causes patient lack of compliance due to a long time of treatment with a total of 30-80 injections administered over years. In this article we deal with the characterization of different MS-PLGA formulations containing BV proteins for VIT. The PLGA microspheres containing BV represent a strategy to replace the multiple injections, because they can control the solute release. Physical and biochemical methods were used to analyze and characterize their preparation. Microspheres with encapsulation efficiencies of 49-75% were obtained with a BV triphasic release profile. Among them, the MS-PLGA 34 kDa-COOH showed to be best for VIT because they presented a low initial burst (20%) and a slow BV release during lag phase. Furthermore, few conformational changes were observed in the released BV. Above all, the BV remained immunologically recognizable, which means that they could continuously stimulate the immune system. Those microspheres containing BV could replace sequential injections of traditional VIT with the remarkable advantage of reduced number of injections. (C) 2011 Elsevier B.V. All rights reserved.

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Remote sensing has a high potential for environmental evaluation. However, a necessity exists for a better understanding of the relations between the soil attributes and spectral data. The objective of this work was to analyze the spectral behavior of some soil profiles from the region of Piracicaba, São Paulo State, using a laboratory spectroradiometer (400 to 2500 nm). The relations between the reflected electromagnetic energy and the soil physical, chemical and mineralogical attributes were analyzed, verifying the spectral variations of soil samples in depth along the profiles with their classification and discrimination. Sandy soil reflected more, presenting a spectral curve with an ascendant form, opposite to clayey soils. The 1900 nm band discriminated soil with 2:1 mineralogy from the 1:1 and oxidic soils. It was possible to detect the presence of kaolinite, gibbsite, hematite and goethite in the soils through the descriptive aspects of curves, absorption features and reflectance intensity. A relation exists between the weathering stage and spectral data. The evaluation of the superficial and subsuperficial horizon samples allowed characterizing and discriminating the analytical variability of the profile, helping to soil distinguishing and classification.